TR201903705T4 - A node and method for managing a packet data network connection. - Google Patents

Abstract

The exemplary embodiments presented herein relate to a Serving Gateway, a core network node, and a Policy Management and Charging Rules Function, as well as their corresponding methods for managing a Packet Data Network Connection of a wireless device.

Description

DESCRIPTION A NODE FOR MANAGING A PACKET DATA NETWORK CONNECTION AND Description of the Invention Technical Field of the Invention The exemplary embodiments presented herein relate to a Serving Gateway, a core network node, and a Policy Management and Charging Rules Function, as well as corresponding methods for managing a Packet Data Network Connection of a wireless device. Background of the Invention In a typical cellular system, also called a wireless communication network, wireless terminals, also known as mobile stations and/or user equipment units, communicate with one or more core networks via a Radio Access Network (RAN). Wireless terminals can be mobile stations or user hardware units, such as Machine-to-Machine (M2M) devices, Internet of Things devices, mobile phones, also known as "cell" phones, and wireless-capable laptop computers, such as portable, pocket-sized, handheld, embedded, or vehicle-mounted mobile devices, that communicate voice and/or data across a radio access network. A radio access network covers a geographic area divided into cell areas; each cell area is served by a base station, such as a Radio Base Station (RBS), also called a "NodeB" or "Node B" or "Enhanced NodeB" or "eNodeB" in some networks and referred to herein as a base station. A cell is a geographic area where radio coverage is provided by radio base station hardware within a base station area. Each cell is identified by an ID broadcast by the cell within its local radio range. Base stations communicate with user equipment within range of the base stations via an air interface operating at radio frequencies. In some types of radio access networks, several base stations are typically connected to a radio network controller (RNC), typically via landlines or microwaves. This radio network controller, sometimes called a Base Station Controller (BSC), can control and coordinate the various activities of multiple connected base stations. Radio network controllers are typically connected to one or more core networks. The Universal Mobile Telecommunications System (UMTS) is a third-generation mobile communications system developed from the Global System for Mobile Communications (GSM). It is intended to provide advanced mobile communications services based on Wide-Band Code Division Multiple Access (WCDMA) access technology. UMTS Terrestrial Radio Access Network1 (UTRAN) is a radio access network that primarily uses wideband code division multiple access for user equipment units (UEs). The Third Generation Partnership Project (3GPP) is committed to further developing UTRAN and GSM-based radio access network technologies. Long Term Evolution (LTE) with Enhanced Packet Core (EPC) is the newest member of the 3GPP family. ERICSSON: "eDRX impact on GTPV2 for network originated control plane procedure", 3GPP (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, volume CT WG4, no. Vancouver; 20150817 - describes a Delay Tolerant Connection in the Session Establish Response message to notify the MME/SGSN that it is tolerant. Summary of the Invention During the operation of a wireless communication network, there may be situations where core network nodes fail or need to be restarted. During these failures or restarts of core network nodes, different procedures are implemented to keep communication disruptions to a minimum. An example of such a procedure is the Service Restoration procedure in 3GPP TS 23.007, PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES; F-. In such a procedure, a node called a Serving Gateway (SGW) detects that a mobility management node, such as a Mobility Management Entity (MME) or a Serving General Packet Radio Service Support Node (SGSN), has failed, and the SGW will need to maintain the PDN connection. Then, when the SGW receives any downlink data for the wireless device, it will broadcast a Downlink Data Notification to the IMSI of the wireless device associated with the PDN connection. However, with a new mechanism recently developed specifically for machine-type wireless devices, where the wireless device can use extended DRX or enter Power Save Mode, the device is not able to listen for the paging request; in this case, the paging triggered upon receiving downlink data is meaningless, merely generating additional signaling in the network. This wireless device typically uses this delay-tolerant service, meaning the service may be delayed until the wireless device is reachable by the network. However, this does not prevent the use of a non-delay-tolerant service. Furthermore, there is currently no means to provide dynamic or updated information regarding whether a PDN connection is delay-tolerant or not, depending on which types of services the wireless device is permitted to use. Furthermore, there are currently no specifications for how this delay-tolerant attribute of a PDN connection affects the management of a PDN connection in the event of a mobility management node failure or restart. Therefore, at least one objective of the example embodiments presented herein is to provide an effective mechanism when the Network Triggered Service Restoration procedure is implemented in a communication network where the wireless device may be in an extended DRX or Power Save Mode. Specifically, one objective of the example embodiments presented herein is to manage a PDN connection of a wireless device to a network implementing the Network Triggered Service Restoration Procedure in the event of an inability management node failure or restart. At least one advantage of the example embodiments presented herein is to reduce unnecessary signaling. Based on the ability of a PDN connection associated with a wireless device to receive delayed communications, the PDN connection may or may not be maintained in the event of a mobility management node failure or restart. Furthermore, another exemplary advantage is that delay tolerance changes due to service or application usage can be taken into account in managing the PDN connection. Accordingly, some exemplary embodiments are directed to a method in an SGW for managing a PDN connection of a wireless device. The SGW is configured to support a Network Triggered Service Restoration Procedure. The method includes receiving a Delay Tolerant Link Indicator (DTCI) from a PDN Gateway indicating whether communication over a designated PDN connection to the wireless device can be delayed. The method further includes recording the DTCI in the SGW. The method also includes managing the PDN connection upon detection of a failure of a mobility management node serving the wireless device (with or without reboot). If the DTCI indicates that the PDN connection is delay tolerant, management includes deleting the PDN connection. If the DTCI also indicates that the PDN connection is not delay tolerant, management includes maintaining the PDN connection. Some example embodiments are for an SGW to manage a PDN connection of a wireless device. The SGW is configured to support a Network Triggered Service Restoration Procedure. The SGW includes a processor and a memory. The memory contains processor-executable commands, whereby the SGW has the functionality to receive a DTCI from a PDN gateway indicating whether communication over a designated PDN connection to the wireless device can be delayed. The SGW also has the functionality to register the DTCI with the SGW. The SGW also has the functionality to manage the PDN connection when a failure (with or without a reboot) of a mobility management node serving the wireless device is detected. In managing the PDN connection, the SGW has the functionality to delete the PDN connection if the DTCl indicates that the PDN connection is delay-tolerant. Alternatively, if the DTCl indicates that the PDN connection is not delay-tolerant, the SGW has the functionality to resume the PDN connection. Some examples of non-claimed rights relate to a method in a core network node for dynamically managing a PDN connection of a wireless device. The core network node contains a registered DTCI that indicates whether the wireless device's communication over a designated PDN connection can be delayed. The method includes receiving, from a PCRF or other core network node, an updated DTCI indicating a changed state regarding whether an identified PDN connection of the wireless device is delay tolerant. The method also includes registering the updated DTCI in the core network node. Some non-claimed examples are for a core network node to dynamically manage a PDN connection of a wireless device. The core network node includes a registered DTCI indicating whether the wireless device can be delayed in communicating over an identified PDN connection. The core network node includes a processor and a memory. The memory contains instructions executable by the processor; By means of these commands, the core network node has the function of receiving, from a PCRF or another core network node, an updated DTCI indicating a changed state regarding whether the wireless device's identified PDN connection is delay tolerant. The core network node also has the function of registering the updated DTCI with the core network node. Some examples, for which no rights are claimed, are directed to a method in a PCRF for dynamically managing a PDN connection of a wireless device. The method includes detecting a state change in the delay tolerance of the PDN connection. The state change represents a change regarding whether the wireless device's identified PDN connection is capable of receiving delayed communications. The method further includes updating a DTCI based on the detected state change. The method further includes sending the updated DTCI to a PGW. Some non-claimed examples are for a PCRF for dynamically managing a PDN connection of a wireless device. The PCRF includes a processor and a memory. The memory includes processor-executable commands by which the PCRF is capable of detecting a state change in the delay tolerance of the PDN connection. The state change represents a change in whether the wireless device's identified PDN connection is capable of receiving delayed communication. The PCRF further includes the functionality of updating a DTCI based on the detected state change. The PCRF also has the functionality of sending the updated DTCI to a PDN gateway (PGW). Abbreviations 3GPP Third Generation Partnership Project AS Application Server BSC Base Station Control Unit DRX Discontinuous Reception DTCI Delay Tolerant Link Indicator E-UTRAN Enhanced Universal Terrestrial Radio Access Network eNodeB Enhanced NodeB EPC Enhanced Packet Core GERAN GSM/EDGE Radio Access Network GGSN Gateway GPRS Support Node GTP GPRS Tunneling Protocol GSM Global System for Mobile Communications HSS Master Subscriber Server International Mobile Subscriber Identity Internet of Things Long Term Evolution Machine-to-Machine Mobility Management Entity Policy Management and Charging Rules Function Packet Data Network PDN Gateway Radio Access Network Routing Area Update Radio Base Station Radio Network Control Unit Radio Resource Management Serving GPRS Support Node Serving Gateway Monitoring Area Update User Hardware Universal Mobile Telecommunications System UMTS Terrestrial Radio Access Network Wideband Code Division Multiple Access Brief Description of the Drawings The foregoing will become clear from the following more specific description of the exemplary embodiments shown in the accompanying drawings, in which like reference characters indicate the same parts throughout the different views. The drawings are not necessarily to scale; on the contrary the emphasis is on the description of the exemplary embodiments. Figure 1 is an illustrative example of a wireless network; Figure 2 is a message passing diagram depicting management of a PDN connection during a mobility procedure including relocation of an SGW, according to some exemplary embodiments presented herein; Figure 3 is a message passing diagram depicting management of a PDN connection including dynamically updating a DTCl, according to some exemplary embodiments presented herein; Figure 4 is an example node configuration of an SGW, core network node, and a PCRF according to some example embodiments; Figure 5A is a flow diagram depicting example operations that can be executed by the SGW according to some example embodiments; Figure 5B is a module diagram depicting modules configured to execute the operations of Figure 5A according to some example embodiments; Figure 6A is a flow diagram depicting example operations that can be executed by the core network node according to some examples; Figure 6B is a module diagram depicting modules configured to execute the operations of Figure 6A according to some examples; Figure 7A is a flow diagram depicting exemplary processes that can be executed by the PCRF according to some examples, and Figure 7B is a module diagram depicting modules configured to execute the processes of Figure 7A according to some examples. Detailed Description of the Invention In the following description, specific details such as specific components, elements, techniques, etc., are set forth for the purpose of non-limiting description to provide a complete understanding of the exemplary embodiments. However, it will be obvious to one skilled in the art that the exemplary embodiments can be implemented in other ways that depart from these specific details. In other cases, detailed descriptions of well-known methods and elements have been avoided so as not to obscure the description of the exemplary embodiments. The terminology used herein is for the purpose of describing the exemplary embodiments and is not intended to limit the embodiments presented herein. It should be noted that all of the example embodiments presented herein are applicable to a GERAN, UTRAN, or E-UTRAN based system. It should also be noted that the terms wireless device, wireless terminal, M2M Device, MTC Device, IoT device, and user equipment are used interchangeably. Overview The example embodiments presented herein are for managing a PDN connection in a communication network that supports a Network Triggered service Restoration procedure. To better explain the example embodiments presented herein, a problem will first be identified and discussed. Overview of the communication network Figure 1 provides a general example of a communication network 100. As shown in Figure 1, a user equipment (UE) 101 may communicate with a Universal Terrestrial Radio Access Network (UTRAN) 103, an Enhanced UTRAN (E-UTRAN) ( subsystem) to communicate with an operator or application server 105. When accessing the SCS, AS, or host systems 105, it may communicate with the UTRAN/E-UTRAN/GERAN ( subsystem) subsystem. It should be noted that the network may also include a WiFi subsystem, although not shown in Figure 1. The GPRS subsystem 107 may include a Serving GPRS Support Node (SGSN), also known as Gn/Gp-SGSN, which may be responsible for the transmission of data packets to and from mobile stations within an associated geographic service area. It may also include a Gateway GPRS Support Node (113), which may be responsible for the interface between the GPRS subsystem (113). The EPC subsystem 109 may include a Mobility Management Entity (115), which may be responsible for mobility management, connection management, UE monitoring in idle mode, paging procedures, connection and activation procedures, and small data and message transfer towards the E-UTRAN (104). The EPC subsystem may include a Serving Gateway (SGW) (117), which may be responsible for the routing and transmission of data packets. The EPC subsystem may also include a Packet Data Gateway (PGW) (119) which may be responsible for providing connectivity from the user hardware (). It should be noted that it may also include a Main Subscriber Server (HSS) (119) which may provide both the SGSN (, device identification information, an International Mobile Subscriber Identity (IMSI), subscription information, etc., and an S4-SGSN (110), thus allowing access to the GERAN ( subsystems when the EPC ( is replaced). The network also includes a Policy Management and Charging Rules Function (PCRF) (120). The PCRF (120) covers policy management decisions and flow-based charging management functionality. 3GPP is partly supporting new technical research, namely improvements in Machine Type Communications and other mobile data applications, more precisely The "UE Power Consumption Optimizations (UEPCOP)" section has been completed, which implements extended DRX and wireless device Power Save Mode for wireless devices in standby mode. The wireless device and the network can negotiate the use of extended standby DRX via non-access layer signaling to reduce power consumption while remaining reachable for mobile termination data and/or network-originated procedures within a specified latency period dependent on the DRX cycle value. Applications that want to use extended standby DRX must consider the specific management of mobile-terminated services or data transfers, and in particular, they must consider the delay tolerance of mobile-terminated data. A network-side application can send mobile-terminated data, an SMS, or a device trigger, and be notified that extended standby DRX is available. To negotiate the use of extended standby mode DRX, the wireless device requests the extended standby mode DRX parameters during the connection procedure and the RAU/TAU procedure. The SGSN/MME can accept or reject the wireless device's request to enable extended standby mode DRX. If the SGSN/MME accepts extended standby mode DRX, the SGSN/MME may also provide different values of the extended standby mode DRX parameters requested by the UE based on operator policies. If the SGSN/MME accepts the use of extended standby mode DRX, the wireless device implements extended standby mode DRX based on the received extended standby mode DRX parameters. Wireless If a wireless device requests, via the NAS, that both PSM (requiring an activity period and possibly a periodic TAU timer) and extended standby DRX (with a specific extended standby DRX cycle value) be enabled, it is up to the SGSN/MME to decide one of the following: 1. Enable only PSM, i.e., not accept the extended standby DRX request. 2. Enable only extended standby DRX Enabling DRX, i.e., not accepting an activity period request. 3. Enabling both PSM (i.e., providing an activity period) and extended standby DRX (i.e., providing the extended standby DRX parameters). Deciding between the three above and deciding which activity period, periodic TAU timer, and/or extended standby DRX cycle value to provide to the UE depends on the application based on the local configuration and possibly other information available in the SGSN/MME. The selected method is then used until the next Connect or RAU/TAU procedure is initiated, at which point a new decision can be made. If both extended I-DRX and PSM are enabled, the extended I-DRX cycle must be configured to have multiple paging capabilities while the activity timer is running. In the specific case where the PSM activity time provided by the device is greater than the extended standby mode DRX cycle value provided by the wireless device, the SGSN/MME can enable both PSM and extended standby mode DRX. This allows a wireless device to minimize power consumption during the activity period, for example, when the activity time is slightly longer than typical activity time values of the order of a few minutes. As described in the GTP-C retransmissions documentation, the mobile processes terminated data using the high-latency communication feature. Wireless device power saving/dpi A wireless device can adopt PSM to reduce power consumption. This mode is similar to powering down, but the wireless device remains registered to the network and does not need to reconnect or reestablish PDN connections. To a wireless device in the PSM, the mobile A wireless device using PSM is reachable for mobile-terminated services during the time it is in connected mode and for an Activity Time period after connected mode. Connected mode is caused by a mobile-originated event, such as data transfer or signaling after a periodic TAU/RAU procedure. Therefore, PSM can only handle infrequent mobile-originated and terminating services and can accept a corresponding delay in mobile-terminated communication. Overview of sample embodiments During the operation of a wireless communication network, there may be situations where core network nodes fail or need to be restarted. During these failures or restarts of core network nodes, different procedures are implemented to keep communication disruptions to a minimum. An example of such a procedure is the 3GPP TS Document 23.007 is a Network Triggered Service Restoration procedure, as specified in section 25. In such a procedure, a node called a Serving Gateway (SGW) detects that a mobility management node, such as a Mobility Management Entity (MME) or a Serving General Packet Radio Service Support Node (SGSN), has failed, and the SGW will need to maintain the PDN connection. Subsequently, when the SGW receives any downlink data for the wireless device, the wireless device associated with the PDN connection will be notified. However, with a new mechanism recently developed specifically for machine-type wireless devices, where the wireless device can use extended DRX or enter Power Save Mode, the device is not capable of listening to the paging request; in this case, the paging triggered upon receipt of Downlink Data is meaningless, only generates additional signaling in the network. Furthermore, there is currently no means to provide dynamic or updated information regarding the ability to change whether a PDN connection is delay-tolerant or not, which depends on which types of services the wireless device is allowed to use. In addition, there are currently no specifications on how this delay-tolerant attribute of a PDN connection affects the management of a PDN connection in the event of a mobility management node failure or restart. Therefore, at least one goal of the example embodiments presented here is to provide an effective mechanism for the situation where the Network Triggered Service Restoration procedure is implemented in a communication network where the wireless device may be in an extended DRX or Power Save Mode. In particular, one goal of the example embodiments presented here is to provide an effective mechanism for the situation where the Network Triggered Service Restoration procedure is configured to support the Network Triggered Service Restoration Procedure. How to manage a PDN connection of a wireless device in a network. At least one other objective of the exemplary embodiments is to effectively manage a PDN connection in the event of a mobility management node failure or restart. At least one advantage of the exemplary embodiments presented here is to reduce unnecessary signaling. Based on the ability of a PDN connection associated with a wireless device to receive delayed communications, the PDN connection may or may not be maintained in the event of a mobility management node failure or restart. Furthermore, another exemplary advantage is that delay tolerance changes resulting from service or application usage can be taken into account in managing the PDN connection in the event of a mobility management node failure or restart. This indicator is used by the PGW to indicate that the PDN connection is delay tolerant; for example, The PGW supports receiving a rejection reason from the MME/SGSN via the SGW, indicating that the wireless device is temporarily unreachable due to power saving during a network-initiated procedure, and continuing the network-initiated procedure until the PGW receives the next Change Carrier Request message with the UASI; the request message indicates that the wireless device is reachable for end-to-end signaling for this PDN connection. However, this delay-tolerant connection indication is not used by the SGW. During a mobility procedure involving a change of SGW, during PDN connection management, the SGW should utilize this indication so that when the SGW detects an MME/SGSN failure (MME/SGSN restart or non-restart failure), the SGW The connection will not maintain PDN connections tagged with Delay Tolerant Connection. To ensure this, in addition, this information "PDN connection is tagged with Delay Tolerant Connection" will be transferred to the new SGW during a mobility procedure involving a SGW change, i.e., the inter-MME/SGSN TAU/RAU handover procedure for UEs in standby mode and the inter-MME/SGSN handover procedure for UEs in active/connected mode. This information can be included in the Session Establish Request message originating from the (target) MME/SGSN when the new SGW is contacted, or in the Change Bearer Response message originating from the PGW (the message is the response from the PGW when the new SGW updates itself with the Change Bearer Request message). Figure 2 illustrates the Delay Tolerant Connection during a mobility procedure involving a SGW change. It shows how the Connection Indicator (DTCl) is transferred to the new SGW (SGWZ is the new SGW). The green bold text indicates the first alternative, where the Context transfer procedure (Context Request/Response/Acknowledgement) is used to transfer the DTCI from the old MME/SGSN to the new MME/SGSN, and the new MME/SGSN includes the DTCI in its Session Establishment Request message to the new SGW. The red bold text indicates the second alternative, where the PGW provides the DTCI to the new SGW using the Change Bearer Response. In this option, the DTCl can be changed indirectly, so that in the subsequent signaling, the Session Establishment Response, the new SG must forward the DTCI to the new MME/SGSN. The MME is just one example; the source (old) mobility management node is a The S4-SGSN can be an MME or a Gn/Gp SGSN; the target (new) mobility management node can be an S4-SGSN or an MME. The PGW can be a PGW. The wireless device (UE) can be either in 2G/3G or LTE. Dynamic management of the Delay Tolerance Connected indicator for a specific PDN connection According to prior art methods, a delay tolerance is set per PDN connection and only during PDN connection establishment; it cannot be changed while the PDN connection is active. However, according to the example embodiments presented here, it should be allowed for a PDN connection to be labeled as Delay Tolerant Connection during PDN connection establishment, but to be changed to non-delay tolerant at a later stage, or vice versa. For example: 1. When a wireless device activates a PDN connection, the PCRF is set to the PDN 2. When the wireless device activates a PDN connection, the PCRF may set the PDN connection to be a non-delay tolerant connection if the wireless device has used up its allocated quota or if the wireless device's subscription has changed, for example, by a user through a web portal (when the end user is about to go to sleep). In summary, the setting for Delay Tolerant or not does not depend on whether the wireless device has activated power saving mode or extended DRX, but on whether the UE is using The PCRF must therefore be able to change the setting of the Delay Tolerant Connection indicator while the PDN connection remains active. Figure 3 shows the Delay Tolerant Connection indicator being set during a PDN connection creation procedure, but the PDN connection is then reset to a normal PDN connection using the Update Bearer Request message. If the updated PCRF decision requires bearer creation/deletion, it is possible for the PGW to use the Create/Delete Bearer Request. The red highlighted text indicates the change resulting from this invention. According to some example embodiments, such a change may be based on an application or server change that the wireless device undergoes. Example node configuration Figure 4 shows an example node configuration of a node. Any of the above discussed 4. Examples of such nodes are an SGW ( ), an S4-SGSN ( 110 ), an MME ( 115 ), or a PGW ( ). The node may provide PDN connection management in a communication network in accordance with the exemplary embodiments described herein. The node may include a receiver 401 that may be configured to receive communication data, commands, delay tolerance information, wireless device application or service usage information, and/or messages. The node may also include a transmitter 402 that may be configured to transmit communication data, commands, delay tolerance information, wireless device application or service usage information, and/or messages. It should be noted that the receiver 401 and the transmitter 402 may consist of any number of transceiver, receiver, and/or transmitter units, modules, or circuits. Furthermore, the receiver 401 and it should be noted that transmitter 402 may be in the form of any input or output communication port known in the art. Receiver 401 and transmitter 402 may include RF circuitry and baseband processing circuitry (not shown). The node may also include a processing unit or circuitry 403 configured to process information related to managing a PDN connection, as described herein. The processing circuits 403 may be any suitable type of computing unit, such as a microprocessor, digital signal processor (DSP), field programmable gate array (F PGA), application specific integrated circuit (ASIC), or any other form of circuit or module. The node may also include a memory unit or circuit 405, which may be any suitable type of computer readable memory and may be volatile and/or nonvolatile. The memory 405 may be configured to store received, transmitted, and/or measured data, device parameters, communication priorities, delay tolerance information, wireless Device application or service usage information, and/or executable program commands. Exemplary node operations Figure 5A is a flow diagram depicting exemplary operations that may be executed by the SGW to manage a PDN connection of a wireless device as described herein. It should also be noted that Figure 5A includes some operations indicated by a solid border and some operations indicated by a dashed border. Operations within a solid border are operations covered by the broadest example embodiment. Operations within a dashed border are example embodiments that may be within or part of broader example embodiments, or are additional operations that may be executed in addition to operations within those embodiments. It should be noted that these operations do not need to be executed sequentially. Furthermore, it should be noted that not all operations need to be executed. The example operations may be executed in any order or in any combination. The example operations are also described in at least a non-exhaustive summary of the example embodiments. Note that the numbering in Figure 5A corresponds to the reference numbers described in the "Summary of Example Embodiments" section. Figure SB is a module diagram depicting modules that can execute at least some of the operations of Figure 5A. Figure 6A is a flow diagram depicting example operations that can be executed by a core network node to manage a PDN connection of a wireless device as described herein. Note that Figure 6A includes some operations indicated by a solid border and some operations indicated by a dashed border. The operations enclosed by a solid border are operations covered by the broadest example embodiment. The operations enclosed by a dashed border are example embodiments that may be within or part of broader example embodiments, or are additional operations that may be executed in addition to the operations of those embodiments. Note that these operations do not need to be executed sequentially. Furthermore, it is important to note that not all operations need to be executed. The example operations may be executed in any order or in any combination. The example operations are also described in at least this non-exhaustive summary of the example embodiments. Note that the numbering in Figure 6A corresponds to the reference numbers described in the "Summary of Example Embodiments" section. Figure 6B is a module diagram depicting modules capable of executing at least some of the operations of Figure 6A. Figure 7A is a flow diagram depicting example operations that can be executed by the PCRF to manage a PDN connection of a wireless device as described herein. Note that Figure 7A includes some operations indicated with a solid border and some operations indicated with a dashed border. The operations enclosed within a solid line are those covered by the broadest Example embodiment. The operations within a dashed border are example embodiments that may be part of or within larger example embodiments, or are additional operations that may be executed in addition to the operations of those embodiments. Note that these operations do not need to be executed sequentially. Furthermore, note that not all of the operations need to be executed. The example operations may be executed in any order or in any combination. The example operations are also described in at least this non-exhaustive summary of the example embodiments. Note that the numbering in Figure 7A corresponds to the reference numbers described in the "Summary of Example Embodiments" section. Figure 7B is a module diagram depicting modules that can execute at least some of the operations of Figure 7A. Some of the embodiments described above can be summarized as follows: One embodiment is directed to a method at an SGW for managing a PDN connection of a wireless device. The method includes receiving a DTCI from at least one GTP entity indicating whether communication over an identified PDN connection to the wireless device can be delayed; recording the DTCI at the SGW; and managing the PDN connection when a failure (with or without reboot) of a mobility management node serving the wireless device is detected; wherein the management includes deleting the PDN connection if the DTCI indicates that the PDN connection is delay tolerant, or resuming the PDN connection if the DTCI indicates that the PDN connection is not delay tolerant. It should be noted that not setting the DTCI can also be used in conjunction with other features or other operator policies to determine whether the PDN connection should be maintained. Examples of these features and operator policies are QCI/ARP/APN and similar parameters. The SGW can determine whether the PDN connection should be maintained based on the DTCI, which can include any number of parameters. In one such example, the SGW will store the DTCI and manage the PDN connection based on the stored DTCI value. Unlike prior art methods, the SGW blindly transmits such a value to the mobility management node. In prior art methods, the SGW does not use the DTCI. When using DTCl, the SGW may maintain the PDN connection upon detecting a failure of the mobility management node (with or without a reboot) if the DTCI value indicates that the connection is not delay-tolerant. If the PDN connection is delay-tolerant, the PDN connection will be deleted, meaning the PDN connection is not eligible for network-triggered service restoration. This is to prevent unnecessary call signaling because the wireless device may activate a power-saving mechanism, for example, extended DRX is enabled or enters a power-saving state. The DTCI may be provided in the form of a flag, reason code, or any other indication known in the art. In the method, the at least one GTP entity may be a PGW, and reception may also include receiving the DTCI from the PGW during a PDN connection establishment procedure. According to such example embodiments, the DTCI may be provided, for example, in a Session Establishment Response message during a PDN connection establishment procedure. In the manner in which the reception occurs during a mobility procedure that includes an SGW relocation, the SGW may be a new SGW and the at least one GTP entity may be the new mobility management node that will serve the wireless device when the mobility procedure is completed; the reception further includes receiving the DTCI from the new mobility management node during the mobility procedure. According to such example embodiments, the DTCI may be provided, for example, in a Context Response message. It should be noted that the new mobility management node receives the DTCI from the old mobility management node in a Context Response message. In the method where reception occurs during a mobility procedure that includes an SGW relocation, the SGW may be a new SGW and the at least one GTP entity may be a PGW; reception further includes receiving the (updated) DTCI from the PGW during the mobility procedure. According to such example embodiments, the DTCI may be provided, for example, in a Change Bearer Response message of the PGW. The method may also include receiving a dynamically updated DTCI from the at least one GTP entity. It should be noted that the dynamically updated DTCI may be provided in a Bearer Update/Create/Delete request or in a Change Bearer Response message. According to some example embodiments, such a dynamic update of the DTCI may be based on changes in service or application usage used by the wireless device. It should be noted that such a dynamically updated DTCI may originate from the PCRF and be provided to the SGW via the PGW. In the method, the mobility management node may be an MME, an SGSN, or an S4-SGSN. Some other embodiments described above can be summarized as follows: Another embodiment is directed to an SGW for managing a PDN connection of a wireless device. The SGW includes a processor and a memory, said memory containing commands executable by said processor, by means of which said SGW has the function of executing: receiving, from at least one GTP entity, a DTCI indicating whether communication over an identified PDN connection to the wireless device can be delayed; Registering the DTCI in the SGW and managing the PDN connection when a failure of a mobility management node serving the wireless device is detected (with or without a reboot); management includes: deleting the PDN connection if the DTCI indicates that the PDN connection is delay-tolerant, or maintaining the PDN connection if the DTCI indicates that the PDN connection is not delay-tolerant. It is important to note that not setting the DTCI can also be used in conjunction with other features or other operator policies to determine whether the PDN connection should be maintained. Examples of these features and operator policies are parameters such as QCI/ARP/APN, and similar parameters. The SGW can determine whether the PDN connection should be maintained based on 10 DTCIs, which can include any number of parameters. According to such an exemplary embodiment, the SGW will record the DTCI and manage the PDN connection based on the stored DTCI value. Unlike prior art methods, the SGW blindly transmits such a value to the mobility management node. In prior art methods, the SGW does not use the DTCI. When using the DTCI, the SGW can resume the PDN connection if the DTCI value indicates that the connection is not delay-tolerant when it detects a failure of the mobility management node (with or without a reboot). If the PDN connection is delay-tolerant, the PDN connection will be deleted, meaning the PDN connection is not eligible for network-triggered service restoration. This is to prevent unnecessary call signaling because the wireless device may activate a power-saving mechanism, for example, by enabling extended DRX or entering a power-saving state. The DTCI may be provided in the form of a flag, reason code, or any other indicator known in the art. With respect to the SGW of this example embodiment, the at least one GTP entity may be a PGW, and the SGW may also have the functionality to receive the DTCI from the PGW during a PDN connection establishment procedure. According to such example embodiments, the DTCI may be provided, for example, in a Session Establish Response message during a PDN connection establishment procedure. With respect to the SGW of this example embodiment, the SGW may have the functionality to receive the DTCI during a mobility procedure that includes an SGW relocation; the SGW may be a new SGW, and the at least one GTP entity may be the new mobility management node that will service the wireless device when the mobility procedure is completed; The SGW may also have the function of receiving the DTCI from the new mobility management node during the mobility procedure. According to such exemplary embodiments, the DTCI may be provided, for example, in a Context Response message. It should be noted that the new mobility management node receives the DTCI from the old mobility management node in a Context Response message. Regarding the SGW of this exemplary embodiment, the SGW may have the function of receiving the DTCI during a mobility procedure involving an SGW relocation; the SGW may be a new SGW and at least one GTP entity may be a PGW; the SGW may also have the function of receiving the DTCI from the (e.g., current) PGW during the mobility procedure. According to such exemplary embodiments, the DTCI may be provided, for example, in a Change Bearer Response message of the PGW. With respect to the SGW of this example embodiment, the SGW may also have functionality to receive a dynamically updated DTCI from at least one GTP entity. It should be noted that the dynamically updated DTCI may be provided in an Update/Create/Delete Bearer request or in a Change Bearer Response message. According to some example embodiments, such a dynamic update of the DTCI may be based on changes in service or application usage used by the wireless device. It should be noted that such a dynamically updated DTCI may originate from the PCRF and be provided to the SGW via the PGW. With respect to the SGW of this example embodiment, the mobility management node may be a Mobility Management Entity, a Serving General Packet Radio Service Support Node (SGSN), or an S4-SGSN. Although terminology derived from 3GPP LTE is used herein to describe the example embodiments, it should be noted that the scope of the example embodiments should not be considered limited solely to the system described above. Other wireless systems, including WCDMA, WiMax, UMB, WiFi, and GSM, may also utilize the example embodiments described herein. The description of the example embodiments provided herein is provided for illustrative purposes. The description is not intended to be exclusive or to limit the precise form in which the example embodiments are described, and modifications and variations are possible based on the foregoing, or may be obtained by applying various alternatives to the given embodiments. The examples discussed herein have been selected and described to illustrate the principles, structure, and practical application of various example embodiments to enable those skilled in the art to use the example embodiments in various ways and with various modifications appropriate for the particular intended use. The features of the embodiments described herein can be combined in all possible combinations of methods, modules, systems, and computer program products. It should be noted that the exemplary embodiments presented herein can be implemented in any combination with each other. It should be noted that the word "a" preceding an element does not necessarily exclude the possibility of multiple such elements. It should also be noted that any reference designations do not limit the scope of the claims, that the exemplary embodiments can be implemented, at least in part, by both hardware and software, and that the use of terminology such as "devices" or "units" or "user equipment" is not limiting. A device or user equipment, as used herein, shall be broadly interpreted to include a cordless telephone having Internet/Intranet access, a web browser, an organizer, a calendar, a camera (e.g., video and/or still image camera), a sound recorder (e.g., a microphone), and/or a global positioning system (GPS) receiver; a personal communication system (PCS) user equipment that may combine a cellular telephone and data processing; an electronic organizer (PDA), which may include a cordless telephone or wireless communication system; a notebook computer; a camera (e.g., video and/or still image camera) with communication capabilities; and any other computing or communication device with transceiving capabilities, such as a personal computer, a home entertainment system, a television, etc. It should be noted that the term user equipment may also include any number of connected devices. It should further be noted that the term user equipment is to be interpreted as any device capable of accessing the Internet or a network. It should further be noted that the term M2M device is to be interpreted as a subclass of user equipment that engages in sporadic communication. The various exemplary embodiments described herein are described in the general context of procedural steps or processes that can be executed by a computer program product in one aspect, the computer program product being embodied in a computer-readable medium containing computer-executable instructions, such as program code, that are executed by computers in networked environments. A computer-readable medium may include removable and non-removable storage devices, including, but not limited to, Read Only Memory (ROM), Random Access Memory (RAM), compact discs (CDs), Digital Versatile Disks (DVDs), etc. Program modules may typically include procedures, programs, objects, components, data structures, etc., that can perform specialized tasks or implement specialized abstract data types. The computer-executable instructions, associated data structures, and program modules represent instances of program code for executing the steps of the procedures described herein. The specific sequence of these executable instructions or associated data structures represents instances of the corresponding actions for implementing the functions described in those steps or operations. Exemplary embodiments are described in the drawings and specification. However, many variations and modifications to these embodiments are possible. Accordingly, although specific terms are used, they are used only in a generic and descriptive sense and are not intended to limit the scope of the invention as defined by the appended claims.TR TR TR TR TR TR

Claims (1)

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